distribute	reads
0-500	50762
500-800	30811
800-1000	17582
1000-1200	15986
1200-1400	14301
1400-1600	13142
1600-1800	12016
1800-2000	10774
2000-2200	9886
2200-2400	9434
2400-2600	8640
2600-2800	8192
2800-3000	7100
>3000	112286
